With development of information and communication technology, an online product sale rate has continually increased.
For online product sale, product providers and product sellers have provided various product sale methods.
In particular, recently, methods of selling products using a product cross-selling method disclosed in Korean Patent application NOs. 10-2009-0002554 and 10-2014-0107031 have been proposed.
Using the product cross-selling method, the product sellers sell products which are not directly provided thereby, thereby creating profit.
However, the conventional product cross-selling method provides a sale agency system using a homepage or increases online product exposure only.
Accordingly, in the conventional product cross-selling method, each of a plurality of product providers cannot freely sell products provided by the other product providers.